I think that is a good guess.
Name: Missouri (RKO Missouri)
Additional Names: Main Street (mid-1940s)/Cinerama (1970s)/Empire
Location: 14th & Main St., Kansas City, MO
Opened: October 30, 1921
Ownership: RKO
Current Status: Closed in 1985. Currently standing, but vacant.
Likely the Empire Theatre, which is still standing and is threatened with demolition as we speak. This theatre was known as the RKO Missouri until 1960, which lines up properly with the date of your ticket stub. It was built in 1921 as the Main Street Theatre.
I think that is a good guess.
Name: Missouri (RKO Missouri)
Additional Names: Main Street (mid-1940s)/Cinerama (1970s)/Empire
Location: 14th & Main St., Kansas City, MO
Opened: October 30, 1921
Ownership: RKO
Current Status: Closed in 1985. Currently standing, but vacant.
I should also add that cinematour.com has photos of the theater, at various stages of its existence. The link:
View link
/theaters/4866/
Likely the Empire Theatre, which is still standing and is threatened with demolition as we speak. This theatre was known as the RKO Missouri until 1960, which lines up properly with the date of your ticket stub. It was built in 1921 as the Main Street Theatre.